[Mike Carr]

NHRA Super Stock (IHRA are the same for these)
SS/AH 6.00 (only 1968 Hemi Cudas and Darts in this class in NHRA; sticks and autos run together)
SS/A 6.00-6.49
SS/B 6.50-6.99
SS/C 7.00-7.49
SS/D 7.50-7.99
SS/E 8.00-8.49
SS/F 8.50-8.99
SS/G 9.00-9.49
SS/H 9.50-9.99
SS/I 10.00-10.99
SS/J 11.00-11.99
SS/K 12.00-12.99
SS/L 13.00-13.99
SS/M 14.00-14.99
SS/N 15.00-15.99
SS/O 16.00-16.99
SS/P 17.00 and more

NHRA SS/GT (IHRA are the same for these)
GT/A 8.00-8.49
GT/B 8.50-8.99
GT/C 9.00-9.49
GT/D 9.50-9.99
GT/E 10.00-10.49
GT/F 10.50-10.99
GT/G 11.00-11.49
GT/H 11.50-11.99
GT/I 12.00-12.49
GT/J 12.50-12.99
GT/K 13.00-13.49
GT/L 13.50-13.99
GT/M 14.00 and more

NHRA GT Truck (IHRA are the same)
GT/TA 9.50-10.49
GT/TB 10.50-11.49
GT/TC 11.50-12.49
GT/TD 12.50 and more

SS/Modified Stock (IHRA only goes to SS/DS)
SS/AS 8.50-9.49 pounds per cid
SS/BS 9.50-10.49
SS/CS 10.50 or more
SS/DS 12 pounds or more; V6 only
SS/ES 15.50 or more, 4 cyl only, max 165 cid
SS/FS 16.50 or more, 155 cid max
SS/GS 18 pounds or more; 4 cly, FWD only, max 230 cid

SS/Modified Truck (IHRA are the same)
Four clases
SS/TA through SS/TD weight breaks mirror SS/AS through SS/DS

Super Stock Modified (IHRA are the same)
SS/AM 7.50-8.49 pounds per cid
SS/BM 8.50-9.49
SS/CM 9.50-10.49
SS/DM 10.50-11.49
SS/EM 11.50-12.49
SS/FM 12.50-13.49
SS/GM 10.50 or more pounds; non-supercharged inline 4 or 6 cylinder and straight 8
11.00 or more pounds, non-supercharged American factory controlled V6

Super Stock Modified X (IHRA are the same)
No V8's allowed in SS/MX
SS/AX 8.50-10.99 pounds per cid
SS/BX 11.00-12.49
SS/CX 12.50 or more
SS/DX 15.00 pounds or more; two turbochargers or OEM supercharger

NHRA Stock Eliminator (IHRA is the same, except where noted)
AA/S 7.50-7.99 (IHRA is 7.00-7.99)
A/S 8.00-8.49
B/S 8.50-8.99
C/S 9.00-9.49
D/S 9.50-9.99
E/S 10.00-10.49
F/S 10.50-10.99
G/S 11.00-11.49
H/S 11.50-11.99
I/S 12.00-12.49
J/S 12.50-12.99
K/S 13.00-13.49
L/S 13.50-13.99
M/S 14.00-14.49
N/S 14.50-14.99
O/S 15.00-15.99
P/S 16.00-16.00
Q/S 17.00-17.99
R/S 18.00-18.99
T/S 19.00-19.99
U/S 20.00 or more (IHRA 20.00-21.99)
V/S 22.00 or more
W/S 24.00 or more

AF/S 13.00-15.99
BF/S 16.00-17.49
CF/S 17.50-18.99
DF/S 19.00-24.99
EF/S 25.oo or more
(sticks and autos run together' stickshift carries a 100 pound penalty in NHRA FWD Stock)